Convert flac to aac (m4a)

flac-to-aac.sh

#!/bin/bash
#
# Convert all .flac music files to .m4a (aac) for itunes/ios use
#
# Install ffmpeg with fdk_aac (uninstall first if built without it):
# $ brew install ffmpeg --with-fdk-aac
#
# The script assumes the following directory structure:
# ./musiikkia/
# ./musiikkia/whatever/song.flac
# ./aac/
# ./aac/whatever/song.m4a
#
# and the script must be run from .
#
# Change occurrences of 'musiikkia' and 'aac' to suit your needs.

find "./musiikkia" -type d -print0 | while IFS= read -r -d '' flacdir
do
    aacdir=`echo "$directory" | sed -e 's/musiikkia\//aac\//'`
    [ -d "$aacdir" ] && continue  # skip if aac-directory exists
    mkdir -p "$aacdir"
done

find "./musiikkia" -name *.flac -print0 | while IFS= read -r -d '' input
do
    output=`echo "$input" | sed -e 's/musiikkia\//aac\//' | sed -e 's/flac$/m4a/'`
    [ -f "$output" ] && continue  # skip if file exists
    echo ""
    echo "$input"
    echo "$output"
    echo ""
    ffmpeg -i "${input}" -c:a libfdk_aac -vbr 3 -vn -n "${output}" < /dev/null
done